Propagation transfer arrangement

ABSTRACT

A propagation transfer arrangement for a high-low temperature flexible mild detonating fuze system having an impulse joint selectively connected to a desired portion of a fuze line. The impulse joint includes a base member and an anvil, both grooved or recessed to receive the fuze line desired portion, and a cap for securing the anvil within the base member. The base member has a firing pin, responsive to radial expansion of the fuze line desired portion in a transverse direction and opposite to or away from the anvil, for striking a detonator to ignite an end transfer assembly of a second high-low temperature flexible mild detonating fuze line.

Elited t es atent Travor [75] Inventor: Bruce W. Travor, Holland, Pa. [73] Assignee: The United States of America as represented by the Secretary of the Army, Washington, DC. [22] Filed: Feb. 2, 1973 [21] Appl. No.: 328,989

[52] US. Cl. 102/27 R, 102/70 [51] Int. Cl C06c 5/06 [58] Field of Search 102/22, 27, 29, 70; 89/1 B [56] References Cited UNITED STATES PATENTS 3,129,663 4/1964 Schnepfe, Jr. 102/27 3,205,818 9/ l 965 Coulson 3,411,401 11/1968 Harris i. 102/27 3,460,477 8/1969 Heidemann et al 102/27 PROPAGATHON TRANSFER ARRANGEMENT Feb. 5, 1974 3,610,151 10/1971 Nett 102/29 Primary Examiner-Verlin R. Pendegrass Attorney, Agent, or Firm-Edwar .1. Kelly; Herbert Berl; William Sommer [57] ABSTRACT A propagation transfer arrangement for a high-low temperature flexible mild detonating fuze system having an impulse joint selectively connected to a desired portion of a fuze line. The impulse joint includes a base member and an anvil, both grooved or recessed to receive the fuze line desired portion, and a cap for securing the anvil within the base member. The base I member has a firing pin, responsive to radial expansion of the fuze line desired portion in a transverse direction and opposite to or away fromthe anvil, for

striking a detonator to ignite an end transfer assembly of a second high-low temperature flexible mild detonating fuze line.

3 Claims, 4 Drawing Figures PROPAGATION TRANSFER ARRANGEMENT The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to mild detonating fuzes and, more particularly, to a propagation transfer arrangement for a high-low temperature flexible mild detonating fuze system.

Prior techniques in transferring mild detonating fuze line propagations required breaks in the line and installation of fittings to hold the end transfer portions of the fuze lines in contact with each other. The shock wave would propagate from the source of initiation to the end transfer, and detonate the integral end transfer for continuation of propagation. However, the interface of the end transfer to the mild detonating fuze ends required exact alignment and control of dimensions to insure continuation of propagation. Further, there existed possible degradation of the shock wave such that it would terminate after a few transfers.

It is an object of this invention to provide a propagation transfer arrangement for a mild detonating fuze system .in which in line discontinuities are eliminated, thus increasing system reliability.

Another object of the invention is to provide such an arrangement having a versatile impulse joint connection which is removable without adversely affecting the system.

A further object of the invention is to provide such an arrangement which is easy and inexpensive to manufacture.

These and other objects, features and advantages will FIG.- 3 is a sectional view taken along line 3-3 of FIG. 2.

FIG. 4 is an enlarged sectional view of the preferred type of flexible mild detonating fuze line in the FIG. 1 arrangement. I

The propagation transfer arrangement, shown generally at 10 (FIG. 1) is particularly useful for a high-low temperature flexible mild detonating fuze system having a flexible mild detonating fuze line 11 with a predetermined direction of propagation. The arrangement has impulse joint apparatus for selective connection to a predetermined portion of fuze line 11 and the impulse joint includes a base member 12(FIGS. 1,2,3) having at one end a longitudinally extending recess or transverse slot 13 of predetermined configuration and length to accommodate a mating anvil 14 which seats in and substantially fills the recess 13. The base of the recess 13 has a transversely extending arcuate groove 15 to seat the predetermined portion of the fuze line 11. The base portion of the anvil 14 also has a transversely extending arcuate recess 16 that mates with groove 15 to define a transverse substantially cylindrical passage for accommodating the fuze line predetermined portion. A pair of diametrically opposed arcuate grooves 18, 19 extend longitudinally along corresponding opposed sidewalls of recess or slot 13 and slidingly receive a corresponding triangularly shaped protuberance 20 that extends outwardly from opposed sidewalls of the anvil 14 to key theanvil against lateral movement within the base member slot or recess 13. An internally threaded cap 21 is secured to theexternally threaded upper end of the base member 12 for contacting the anvil 14 to bias the arcuate recess 16 and arcuate groove 15 toward each other to clamp upon opposed peripheral portions of the desired connection area of fuze line 11. I

At the other end of the base member 12 there is provided a downwardly opening longitudinally extending cylindrical recess 23, the base portion 24 of which intersects at least a central portion of the arcuate groove 15 to define a communicative passage therebetween. A firing pin 25 slidably mounted in recess 23 is seated adjacent base 24 and held by shear pin 26 that threadedly secures in an intermediate portion of base member 12 and extends within an appropriate transverse opening in the firing pin 25 rearwardly of its O-ring seal 27.

A detonator housing 30 has an internally threaded recess 31 at one end for attachment to the externally threaded lower end 28 of base member 12. A centralpassage 33 fluidly communicates the interior of recess 23 with detonator 34 for reception of the firing pin tip. At the other end of the detonator housing a downwardly opening cylindrical recess 35 accommodates a second flexible mild detonating fuze line 36 and the end transfer assembly 37 secured therein and positioned adjacent and in alignment with detonator 34. The securing nut 39 for fuzeline 36 threadedly attaches to the reduced externally threaded lower end portion of the detonator housing 30.

The preferred type of high-low temperature flexible mild detonating fuz'e line to be utilized in the system has a high-low temperature core 41 (FIG.4) of PETN or equivalent such as DIPAM. Core 41 is surrounded by a lead sheathing 42 that in turn is successively surrounded by five (5) layers of braided fiber glass 43 and an inner and outer layer of heat shrinkable tubing 44, 45.

Upon actuation of fuze line 11 and as ignition reaches the attached impulse joint, 'the portion of line within central portion of the groove 15 expands radially with much force in a direction away from anvil 14. The radial expansion is directed onto the rearward surface of firing pin 25, which in turn receives sufficient energy to shear the pin 26 and strike detonator 34 and continue the high level propagation through fuze line 36 in addition to the uninterrupted propagation continuation existing in fuze line 11.

Various modifications, changes or alterations may be resorted to without departing from the scope of the invention as defined in the appended claims.

I claim:

1. In a propagation transfer arrangement for a highlow temperature flexible mild detonating fuze system having a flexible mild detonating fuze line with a predetermined direction of propagation,

an impulse joint apparatus for selective connection to a predetermined portion of said fuze line and having a base member with a longitudinal recess at one end thereof, a transversely extending arcuate groove in the base of said recess for seating said fuze line portion, an anvil seated in and substantially filling said recess and having a base portion containing an arcuate recess extending transversely of said base portion and mating with said groove for accommodating said fuze line portion, means longitudinally keying said anvil and said base member one end against relative lateral movement, an internally threaded cap secured to said base member one end for contacting said anvil to bias said arcuate recess and arcuate groove toward each other, said base member having another end containing a longitudinally extending, cylindrical recess the base of which intersects at least a central portion of said arcuate groove and seats a firing pin slidably mounted in said cylindrical recess, and a shear pin mounted in said base member and extending transversely into said firing pin,

detonator housing secured to said base member other end and containing a detonator in fluid communication with said firing pin, and

an end transfer assembly of a second flexible mild detonating fuze line secured within said detonator housing adjacent said detonator.

2. The structure in accordance with claim 1 wherein said keying means includes a pair of diametrically 0pposed arcuate grooves extending longitudinally along heat shrinkable tubing. 

1. In a propagation transfer arrangement for a high-low temperature flexible mild detonating fuze system having a flexible mild detonating fuze line with a predetermined direction of propagation, an impulse joint apparatus for selective connection to a predetermined portion of said fuze line and having a base member with a longitudinal recess at one end thereof, a transversely extending arcuate groove in the base of said recess for seating said fuze line portion, an anvil seated in and substantially filling said recess and having a base portion containing an arcuate recess extending transversely of said base portion and mating with said groove for accommodating said fuze line portion, means longitudinallY keying said anvil and said base member one end against relative lateral movement, an internally threaded cap secured to said base member one end for contacting said anvil to bias said arcuate recess and arcuate groove toward each other, said base member having another end containing a longitudinally extending, cylindrical recess the base of which intersects at least a central portion of said arcuate groove and seats a firing pin slidably mounted in said cylindrical recess, and a shear pin mounted in said base member and extending transversely into said firing pin, a detonator housing secured to said base member other end and containing a detonator in fluid communication with said firing pin, and an end transfer assembly of a second flexible mild detonating fuze line secured within said detonator housing adjacent said detonator.
 2. The structure in accordance with claim 1 wherein said keying means includes a pair of diametrically opposed arcuate grooves extending longitudinally along opposed sidewalls of said base member one end recess and slidingly receiving a corresponding triangularly shaped protuberance extending outwardly from opposed sidewalls of said anvil.
 3. The structure according to claim 1 wherein the mild detonating fuze material includes a high-low temperature core successively surrounded by a lead sheathing, a plurality of braided fiber glass layers, and heat shrinkable tubing. 